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Synthesis, Composition Optimization, and VUV Photoluminescence Characterization of (Y,Gd)(V,P)O_4∶Eu^(3+) as A Potential Red-Emitting Plasma-Display Panel Phosphor
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作者 吴佳蓁 郑炳铭 陈登铭 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期257-261,共5页
The synthesis, composition optimization, VUV Photoluminescence (PL) spectra, and optical properties, of (Y,Gd)(V,P)O4∶Eu3+ phosphors were investigated by synchrotron radiation. The VUV PLE spectra and the correlation... The synthesis, composition optimization, VUV Photoluminescence (PL) spectra, and optical properties, of (Y,Gd)(V,P)O4∶Eu3+ phosphors were investigated by synchrotron radiation. The VUV PLE spectra and the correlation among VUV PL intensity, λem, and Eu3+, Gd3+, and P-content were established. The PLE spectral studies showed that (Y,Gd)(V,P)O4∶Eu3+ exhibited significant absorption in the VUV range. The VUV PL intensity was found to enhance with PO43- and Gd3+-doping. Furthermore, the chromaticity characteristics of (Y,Gd)(V,P)O4∶Eu3+ were also found to be (0.6614, 0.3286) and compared against (Y, Gd)BO3∶Eu3+ as a reference. Based on the characterization results, we are currently improving and evaluating the potential application of (Y,Gd)(V,P)O4∶Eu3+ as a new red-emitting PDP phosphor. 展开更多
关键词 PHOSPHORS VUV spectra CIE chromaticity coordinates plasma-display panel rare earths
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基因panel在新生儿疑似遗传代谢疾病中的应用
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作者 魏莹 容志惠 陈玲 《医药导报》 CAS 北大核心 2024年第12期1965-1970,共6页
目的探讨基因panel在患有疑似遗传代谢疾病新生儿中的应用。方法对华中科技大学同济医学院附属同济医院2023年1月—2024年3月收治的有遗传代谢高危临床表型的新生儿,采用基因panel检测,同时搜集其临床资料并进行随访观察,分析致病基因... 目的探讨基因panel在患有疑似遗传代谢疾病新生儿中的应用。方法对华中科技大学同济医学院附属同济医院2023年1月—2024年3月收治的有遗传代谢高危临床表型的新生儿,采用基因panel检测,同时搜集其临床资料并进行随访观察,分析致病基因的检出情况、患儿基因型与表型的一致性等。结果该研究共纳入53例有遗传代谢高危征象的新生儿,其中致病基因阳性的总体检出率为17.0%(9/53),常见检出的致病基因有氯离子通道基因(CLCN1)、双氧化酶2基因(DUOX2)、间隙连接蛋白β2基因(GJB2)、酪氨酸蛋白磷酸酶非受体11型基因(PTPN11)、钠通道α亚基基因(SCN1A)、痉挛截瘫基因11(SPG11)等,其中DUOX2和GJB2检出比例最高,分别为33.3%(3/9)和22.2%(2/9)。将致病基因阳性组患儿与阴性组患儿进行对比分析,阳性组患儿临床表型个数可能更多,预后相较于基因阴性组也更严重。在致病基因阳性组患儿中,除了病例1和病例9因相关疾病发病较晚导致临床表型与致病基因暂时不相符,其余病例致病基因与临床表型均符合。结论基因panel具有耗时短、检测成本及技术难度低等特点,适用于发展中国家及经济水平相对落后地区疑似遗传代谢疾病患儿的早期筛查。 展开更多
关键词 基因panel 遗传代谢病 基因检测 新生儿 早期筛查
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Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model 被引量:1
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作者 Er-feng Zhao Xin Li Chong-shi Gu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期177-186,共10页
Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and ... Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in China.Subsequently,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect characteristics.These findings revealed the governing mechanism of main factors.Furthermore,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch dams.This model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation differences.Ultimately,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam performance.Additionally,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably interpreted.Validation of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan dam.The findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures. 展开更多
关键词 Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion panel data model
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Energy dissipation mechanism and ballistic characteristic optimization in foam sandwich panels against spherical projectile impact
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作者 Jianqiang Deng Tao Liu +4 位作者 Liming Chen Xin Pan Jingzhe Wang Shaowei Zhu Weiguo Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期108-122,共15页
This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element method.Based on th... This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element method.Based on the geometric topology of the FSP system,three FSP configurations with the same areal density are derived,namely multi-layer,gradient core and asymmetric face sheet,and three key structural parameters are identified:core thickness(t_(c)),face sheet thickness(t_(f))and overlap face/core number(n_(o)).The ballistic performance of the FSP system is comprehensively evaluated in terms of the ballistic limit velocity(BLV),deformation modes,energy dissipation mechanism,and specific penetration energy(SPE).The results show that the FSP system exhibits a significant configuration dependence,whose ballistic performance ranking is:asymmetric face sheet>gradient core>multi-layer.The mass distribution of the top and bottom face sheets plays a critical role in the ballistic resistance of the FSP system.Both BLV and SPE increase with tf,while the raising tcor noleads to an increase in BLV but a decrease in SPE.Further,a face-core synchronous enhancement mechanism is discovered by the energy dissipation analysis,based on which the ballistic optimization procedure is also conducted and a design chart is established.This study shed light on the anti-penetration mechanism of the FSP system and might provide a theoretical basis for its engineering application. 展开更多
关键词 Sandwich panel Numerical simulation Ballistic resistance Specific penetration energy Energy analysis
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Impact of Different Rooftop Coverings on Photovoltaic Panel Temperature
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作者 Aws Al-Akam Ahmed A.Abduljabbar Ali Jaber Abdulhamed 《Energy Engineering》 EI 2024年第12期3761-3777,共17页
Photovoltaic(PV)panels are essential to the global transition towards sustainable energy,offering a clean,renewable source that reduces reliance on fossil fuels and mitigates climate change.High temperatures can signi... Photovoltaic(PV)panels are essential to the global transition towards sustainable energy,offering a clean,renewable source that reduces reliance on fossil fuels and mitigates climate change.High temperatures can significantly affect the performance of photovoltaic(PV)panels by reducing their efficiency and power output.This paper explores the consequential effect of various rooftop coverings on the thermal performance of photovoltaic(PV)panels.It investigates the relationship between the type of rooftop covering materials and the efficiency of PV panels,considering the thermal performance and its implications for enhancing their overall performance and sustainability.The study compares four rooftop covering materials:wooden flakes packs(both dry and wet),polystyrene,and woolen insulation.The measurements were implemented under Iraqi weather conditions.The comparison was based on the PV panels’thermal behavior and its impact on conversion efficiency.The results revealed that covering the roof beneath the installed PV panels reduces their temperature and increases efficiency.The best performance was observedwhen placingwetwooden flakes beneath the panels,with an efficiency increase of 5%.Moreover,thewoolen insulation offered an efficiency rise of 12%near sunset.Themain outcome of thiswork is that the wet–wooden–flakes showed the best performance improvement of the PV panels. 展开更多
关键词 Solar energy PV panels thermal performance rooftop covering
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How R&D investment promotes green technology innovation in the context of digitalization?-An empirical analysis based on provincial panel data
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作者 LIU Jie LI Zhi-hui WEI Fang-xin 《Ecological Economy》 2024年第1期39-52,共14页
Green technology innovation is an important driving force and source to promote my country’s high-quality development,and it is the core path to achieve sustainable development.This paper uses my country’s provincia... Green technology innovation is an important driving force and source to promote my country’s high-quality development,and it is the core path to achieve sustainable development.This paper uses my country’s provincial panel data from 2016 to 2019 to study the impact mechanism of R&D investment on green technology innovation,and introduces the level of digitization,using the panel threshold model to discuss its role in the impact mechanism of R&D investment on green technology innovation.The study found that when the level of digitalization in a region is low,increasing R&D investment does not necessarily improve the ability of green technology innovation;when the level of digitalization is relatively high,R&D investment has a positive role in promoting green technology innovation.Therefore,it is necessary to improve policies to encourage enterprises to increase investment in research and development;at the same time,it is necessary to promote the coordinated development of digital foundation,digital investment,digital literacy,digital economy and digital application,and promote the deep integration of digitalization and green technology innovation. 展开更多
关键词 green technology innovation R&D investment digital level panel model
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Advancements in Photovoltaic Panel Fault Detection Techniques
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作者 Junyao Zheng 《Journal of Materials Science and Chemical Engineering》 2024年第6期1-11,共11页
This paper examines the progression and advancements in fault detection techniques for photovoltaic (PV) panels, a target for optimizing the efficiency and longevity of solar energy systems. As the adoption of PV tech... This paper examines the progression and advancements in fault detection techniques for photovoltaic (PV) panels, a target for optimizing the efficiency and longevity of solar energy systems. As the adoption of PV technology grows, the need for effective fault detection strategies becomes increasingly paramount to maximize energy output and minimize operational downtimes of solar power systems. These approaches include the use of machine learning and deep learning methodologies to be able to detect the identified faults in PV technology. Here, we delve into how machine learning models, specifically kernel-based extreme learning machines and support vector machines, trained on current-voltage characteristic (I-V curve) data, provide information on fault identification. We explore deep learning approaches by taking models like EfficientNet-B0, which looks at infrared images of solar panels to detect subtle defects not visible to the human eye. We highlight the utilization of advanced image processing techniques and algorithms to exploit aerial imagery data, from Unmanned Aerial Vehicles (UAVs), for inspecting large solar installations. Some other techniques like DeepLabV3 , Feature Pyramid Networks (FPN), and U-Net will be detailed as such tools enable effective segmentation and anomaly detection in aerial panel images. Finally, we discuss implications of these technologies on labor costs, fault detection precision, and sustainability of PV installations. 展开更多
关键词 Photovoltaic panels Fault Detection Deep Learning Image Processing
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Composite Panels from the Combination of Rice Husk and Wood Chips with a Natural Resin Based on Tannins Reinforced with Sugar Cane Molasses Intended for Building Insulation: Physico-Mechanical and Thermal Properties
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作者 Paul Nestor Djomou Djonga Rosellyne Serewane Deramne +2 位作者 Gustave Assoualaye Ahmat Tom Tégawendé Justin Zaida 《Journal of Materials Science and Chemical Engineering》 2024年第2期19-30,共12页
The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips an... The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips and husks are materials which can have good thermal conductivity and therefore the combination of these precursors could make it possible to obtain panels with good insulating properties. With regard to environmental and climatic constraints, the composite panels formulated at various rates were tested and the physico-mechanical and thermal properties showed that it was essential to add a crosslinker in order to increase certain solicitation. an incorporation rate of 12% to 30% made it possible to obtain panels with low thermal conductivity, a low surface water absorption capacity and which gives the composite good thermal insulation and will find many applications in the construction and real estate sector. Finally, new solutions to improve the fire reaction of the insulation panels are tested which allows to identify suitable solutions for the developed composites. In view of the flame tests, the panels obtained are good and can effectively combat fire safety in public buildings. 展开更多
关键词 Composite panels Tannins Reinforced Sugar Cane Molasses Building Insulation Mechanical and Thermal Properties
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A Modified Principal Component Analysis Method for Honeycomb Sandwich Panel Debonding Recognition Based on Distributed Optical Fiber Sensing Signals
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作者 Shuai Chen Yinwei Ma +5 位作者 Zhongshu Wang Zongmei Xu Song Zhang Jianle Li Hao Xu Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2024年第2期125-141,共17页
The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scatt... The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scattering have been extensively deployed in structural health monitoring due to their advantages,such as lightweight and ease of embedding.However,identifying the precise location of damage from the optical fiber signals remains a critical challenge.In this paper,a novel approach which namely Modified Sliding Window Principal Component Analysis(MSWPCA)was proposed to facilitate automatic damage identification and localization via distributed optical fiber sensors.The proposed method is able to extract signal characteristics interfered by measurement noise to improve the accuracy of damage detection.Specifically,we applied the MSWPCA method to monitor and analyze the debonding propagation process in honeycomb sandwich panel structures.Our findings demonstrate that the training model exhibits high precision in detecting the location and size of honeycomb debonding,thereby facilitating reliable and efficient online assessment of the structural health state. 展开更多
关键词 Structural health monitoring distributed opticalfiber sensor damage identification honeycomb sandwich panel principal component analysis
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Comprehensive Examination of Solar Panel Design: A Focus on Thermal Dynamics
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作者 Kajal Sheth Dhvanil Patel 《Smart Grid and Renewable Energy》 2024年第1期15-33,共19页
In the 21st century, the deployment of ground-based Solar Photovoltaic (PV) Modules has seen exponential growth, driven by increasing demands for green, clean, and renewable energy sources. However, their usage is con... In the 21st century, the deployment of ground-based Solar Photovoltaic (PV) Modules has seen exponential growth, driven by increasing demands for green, clean, and renewable energy sources. However, their usage is constrained by certain limitations. Notably, the efficiency of solar PV modules on the ground peaks at a maximum of 25%, and there are concerns regarding their long-term reliability, with an expected lifespan of approximately 25 years without failures. This study focuses on analyzing the thermal efficiency of PV Modules. We have investigated the temperature profile of PV Modules under varying environmental conditions, such as air velocity and ambient temperature, utilizing Computational Fluid Dynamics (CFD). This analysis is crucial as the efficiency of PV Modules is significantly impacted by changes in the temperature differential relative to the environment. Furthermore, the study highlights the effect of airflow over solar panels on their temperature. It is found that a decrease in the temperature of the PV Module increases Open Circuit Voltage, underlining the importance of thermal management in optimizing solar panel performance. 展开更多
关键词 Solar Photovoltaic (PV) Modules Thermal Efficiency Analysis Open Circuit Voltage Computational Fluid Dynamics (CFD) Solar panel Temperature Profile
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血清外泌体microRNAs单一及组合panel对结直肠癌的诊断价值 被引量:3
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作者 郝剑 韩磊 《实用医学杂志》 CAS 北大核心 2023年第3期369-373,共5页
目的 检测血清外泌体miR-15b、miR-16、miR-21和miR-31在结直肠癌患者中的表达水平,并评估其对结直肠癌的诊断价值。方法 选取2018年3月至2022年5月本院收治的123例直肠癌患者(结直肠癌组)及117例大肠腺瘤患者作为研究对象(结直肠癌组)... 目的 检测血清外泌体miR-15b、miR-16、miR-21和miR-31在结直肠癌患者中的表达水平,并评估其对结直肠癌的诊断价值。方法 选取2018年3月至2022年5月本院收治的123例直肠癌患者(结直肠癌组)及117例大肠腺瘤患者作为研究对象(结直肠癌组),并纳入150例健康对照者作为对照(健康对照组)。提取血清外泌体中miR-15b、miR-16、miR-21和miR-31,qRT-PCR比较4种miRNA在各组中表达水平差异。受试者工作特征(ROC)曲线评价4种miRNA单一及组合panel对结直肠癌的诊断价值。结果 结直肠癌组血清miR-15b、miR-16、miR-21和miR-31水平高于健康对照组(P <0.05),且miR-15b、miR-21和miR-31水平高于结直肠腺瘤组(P <0.05)。Ⅲ-Ⅳ期、伴淋巴结浸润、低分化程度结直肠癌组患者血清miR-15b、miR-21和miR-31水平分别高于Ⅰ-Ⅱ期、不伴淋巴结浸润、中-高分化程度患者,miR-15b、miR-21和miR-31水平与临床TNM分期、伴淋巴结浸润呈正相关,与分化程度呈负相关。4种miRNA中诊断价值最高的指标是miR-15b,其敏感度和特异度分别为81.33%和91.80%(P <0.05);且miR-15b、miR-21和miR-31的组合panel具有更好的诊断价值,其敏感度和特异度分别为95.06%和94.44%(P <0.05)。结论 miR-15b、miR-16、miR-21和miR-31在结直肠癌患者外周血血清中异常表达,miR-15b、miR-21和miR-31水平与结直肠癌的发病及进展密切相关,且miR-15b、miR-21和miR-31组合panel具有作为结直肠癌的新型诊断模型的潜力。 展开更多
关键词 血清外泌体miRNA 结直肠癌 miRNA panel 诊断价值
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Sensitivity analysis of spacecraft in micrometeoroids and orbital debris environment based on panel method 被引量:3
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作者 Di-qi Hu Run-qiang Chi +1 位作者 Yu-yan Liu Bao-jun Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期126-142,共17页
To reduce the risk of mission failure caused by the MM/OD impact of the spacecraft,it is necessary to optimize the design of the spacecraft.Spacecraft survivability assessment is the key technology in the optimal desi... To reduce the risk of mission failure caused by the MM/OD impact of the spacecraft,it is necessary to optimize the design of the spacecraft.Spacecraft survivability assessment is the key technology in the optimal design of spacecraft.Spacecraft survivability assessment includes spacecraft impact sensitivity analysis and spacecraft component vulnerability analysis under MM/OD environment.The impact sensitivity refers to the probability of a spacecraft encountering an MM/OD impact while in orbit.Vulnerability refers to the probability that each component of a spacecraft may fail or malfunction when impacted by space debris.Yet this paper mainly analyzes the impact sensitivity and proposes a spacecraft sensitivity assessment method under the MM/OD environment based on a panel method.Under this panel method,a spacecraft geometric model is discretized into small panels,and whether they are impacted by MM/OD or not is determined through the analysis of the shielding or shadowing relationships between panels.The number of impacts on each panel is obtained through calculation,and accordingly the probability of each spacecraft component encountering MM/OD impact can be acquired,thus generating the impact sensibility.This paper extracts data from the NASA’s ORDEM2000,the ESA’s MASTER8 as well as the SDEEM2015(Space Debris Environmental Engineering Model developed by HIT),and uses the PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)method to interpolate and fit the size-flux relationship of space debris.Compared with linear interpolation and cubic spline interpolation,the fitting results through the method are relatively more accurate.The feasibility of this method is also demonstrated through two actual examples shown in this paper,whose results are close to those from ESABASE,although there are some minor errors mainly due to different debris data input.Through the cross-check by three risk assessment software-BUMPER,MDPANTO and MODAOST-under standard operating conditions,the feasibility of this method is again verified. 展开更多
关键词 Shielding algorithm panel method SPACECRAFT Sensitivity
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Regulation of the growth of sprouting roots of black locust seedlings using root barrier panels 被引量:1
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作者 Satoshi Kitaoka Shiro Matsunami +4 位作者 Yannan Wang Saki Fujita Kobayashi Makoto Toshiyuki Hirata Takayoshi Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期655-664,共10页
How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increa... How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increases its growing area with sprouting roots and the elongation of horizontal roots at a soil depth of 10 cm.Therefore,a method to regulate the development of horizontal roots could be eff ective in slowing the invasiveness of black locust.In this study,root barrier panels were tested to inhibit the growth of horizontal roots.Since it is labor intensive to observe the growth of roots in the fi eld,it was investigated in a nursery setting.The decrease in secondary fl ush,an increase in yellowed leafl ets,and the height in the seedlings were measured.Installing root barrier panels to a depth of 30 cm eff ectively inhibit the growth of horizontal roots of young black locust. 展开更多
关键词 Black locust Horizontal roots NUTRIENTS Root barrier panel Sprouting roots
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Developing strategy for rural transformation to alleviate poverty in Pakistan:Stylized facts from panel analysis 被引量:1
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作者 ABEDULLAH Shujaat FAROOQ Farah NAZ 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3610-3623,共14页
Sustainable income growth and poverty reduction remain critical challenges at the forefront of research in Pakistan,particularly in rural areas.To overcome these challenges,the role of rural transformation(RT)has emer... Sustainable income growth and poverty reduction remain critical challenges at the forefront of research in Pakistan,particularly in rural areas.To overcome these challenges,the role of rural transformation(RT)has emerged and gained importance in recent years.The present study is based on district-level data and covers the period from 1981 to 2019.The study attempts to quantify the role of rural transformation in boosting rural per capita income and alleviating rural poverty in the country.The study also aims to explore the impact of stages of rural transformation on rural per capita income and rural poverty alleviation.The empirical findings reveal that rural transformation(RT_(1)and RT_(2))is essential in enhancing rural per capita income and alleviating rural poverty.The role of the share of high-value crops(RT_(1))is more pronounced than the share of non-farm employment(RT_(2))in boosting rural per capita income and poverty alleviation.The trend of larger contribution of RT_(1)to enhance rural per capita income also continued at 2nd stage of rural transformation.In the case of poverty reduction,at 3rd stage of rural transformation,the role of RT_(2)is dominant.Our results indicate that districts at higher stages of rural transformation(both RT_(1)and RT_(2))tend to correlate positively with increased rural per capita income and reduced poverty rates,suggesting that progress in rural transformation is associated with improved economic conditions.However,it is important to note that this correlation does not necessarily imply a direct causal relationship between rural transformation and these economic outcomes;other factors may have influenced this relationship.In addition,the welfare impacts are more noticeable among the districts where a simultaneous shift from grain crops to cash crops and from farm employment to non-farm employment is observed.The study provides baseline information to learn experiences from fast-growing districts and to replicate the strategies in other districts,which boosts the RT process that may increase rural per capita income and enhance poverty reduction efforts. 展开更多
关键词 rural transformation rural income rural poverty AGRICULTURE panel analysis
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Ghost-Retina Net:Fast Shadow Detection Method for Photovoltaic Panels Based on Improved Retina Net 被引量:1
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作者 Jun Wu Penghui Fan +1 位作者 Yingxin Sun Weifeng Gui 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1305-1321,共17页
Based on the artificial intelligence algorithm of RetinaNet,we propose the Ghost-RetinaNet in this paper,a fast shadow detection method for photovoltaic panels,to solve the problems of extreme target density,large ove... Based on the artificial intelligence algorithm of RetinaNet,we propose the Ghost-RetinaNet in this paper,a fast shadow detection method for photovoltaic panels,to solve the problems of extreme target density,large overlap,high cost and poor real-time performance in photovoltaic panel shadow detection.Firstly,the Ghost CSP module based on Cross Stage Partial(CSP)is adopted in feature extraction network to improve the accuracy and detection speed.Based on extracted features,recursive feature fusion structure ismentioned to enhance the feature information of all objects.We introduce the SiLU activation function and CIoU Loss to increase the learning and generalization ability of the network and improve the positioning accuracy of the bounding box regression,respectively.Finally,in order to achieve fast detection,the Ghost strategy is chosen to lighten the size of the algorithm.The results of the experiment show that the average detection accuracy(mAP)of the algorithm can reach up to 97.17%,the model size is only 8.75 MB and the detection speed is highly up to 50.8 Frame per second(FPS),which can meet the requirements of real-time detection speed and accuracy of photovoltaic panels in the practical environment.The realization of the algorithm also provides new research methods and ideas for fault detection in the photovoltaic power generation system. 展开更多
关键词 Deep learning intensive object detection photovoltaic panel shadow Ghost module retinanet
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Automated Classification of Snow-Covered Solar Panel Surfaces Based on Deep Learning Approaches
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作者 Abdullah Ahmed Al-Dulaimi Muhammet Tahir Guneser +1 位作者 Alaa Ali Hameed Mohammad Shukri Salman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2291-2319,共29页
Recently,the demand for renewable energy has increased due to its environmental and economic needs.Solar panels are the mainstay for dealing with solar energy and converting it into another form of usable energy.Solar... Recently,the demand for renewable energy has increased due to its environmental and economic needs.Solar panels are the mainstay for dealing with solar energy and converting it into another form of usable energy.Solar panels work under suitable climatic conditions that allow the light photons to access the solar cells,as any blocking of sunlight on these cells causes a halt in the panels work and restricts the carry of these photons.Thus,the panels are unable to work under these conditions.A layer of snow forms on the solar panels due to snowfall in areas with low temperatures.Therefore,it causes an insulating layer on solar panels and the inability to produce electrical energy.The detection of snow-covered solar panels is crucial,as it allows us the opportunity to remove snow using some heating techniques more efficiently and restore the photovoltaics system to proper operation.This paper presents five deep learning models,■-16,■-19,ESNET-18,ESNET-50,and ESNET-101,which are used for the recognition and classification of solar panel images.In this paper,two different cases were applied;the first case is performed on the original dataset without trying any kind of preprocessing,and the second case is extreme climate conditions and simulated by generating motion noise.Furthermore,the dataset was replicated using the upsampling technique in order to handle the unbalancing issue.The conducted dataset is divided into three different categories,namely;all_snow,no_snow,and partial snow.The fivemodels are trained,validated,and tested on this dataset under the same conditions 60%training,20%validation,and testing 20%for both cases.The accuracy of the models has been compared and verified to distinguish and classify the processed dataset.The accuracy results in the first case showthat the comparedmodels■-16,■-19,ESNET-18,and ESNET-50 give 0.9592,while ESNET-101 gives 0.9694.In the second case,the models outperformed their counterparts in the first case by evaluating performance,where the accuracy results reached 1.00,0.9545,0.9888,1.00.and 1.00 for■-16,■-19,ESNET-18 and ESNET-50,respectively.Consequently,we conclude that the second case models outperformed their peers. 展开更多
关键词 Deep learning CNN models image classification solar panels solar panel defect detection
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Indian Solar Panel Initiatives in Reducing Carbon Dioxide Emissions
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作者 Manoj K. Khanna Sarika Malik +1 位作者 Hemant Kumar   Suruchi 《Energy and Power Engineering》 CAS 2023年第4期191-203,共13页
Environmental degradation and the emission of greenhouse gases particularly carbon dioxide have expanded problems to human wellness and to the atmosphere. The second-most populated country in the globe, India, is amon... Environmental degradation and the emission of greenhouse gases particularly carbon dioxide have expanded problems to human wellness and to the atmosphere. The second-most populated country in the globe, India, is among the primary users of conventional resources, which leads to global warming. The growth rate is anticipated to raise more before 2050, which will cause the brisk industrial expansion and rising energy demand to both increases. In order to reduce carbon emissions and meet energy requirements, many countries use alternate usage of renewable energy particularly solar energy. In this review we aim to study solar panel schemes initiated by India, mainly focusing on National Solar Mission. This study also reviews the present solar installed capacity, solar panel scheme 2022, and initiatives and outcomes of solar panels in residences and offices. This study reviewed that by using solar panel resources, the (MNRE) Ministry of New and Renewable Energy hopes to help the Indian Government reach its purpose of 100 GW solar installed capacity by end of 2022. Despite having an amazing 40 GW of solar power installed capacity till December 2021, India is still far from reaching its own goal of 100 GW by March 2023 as per NSM. In essence, this means that India will need to change a few of its ongoing plans further. 展开更多
关键词 Renewable Energy Solar panel Carbon Dioxide Emission Schemes of the Indian Government INITIATIVES
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Feature Extraction and Classification of Photovoltaic Panels Based on Convolutional Neural Network
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作者 S.Prabhakaran R.Annie Uthra J.Preetharoselyn 《Computers, Materials & Continua》 SCIE EI 2023年第1期1437-1455,共19页
Photovoltaic(PV)boards are a perfect way to create eco-friendly power from daylight.The defects in the PV panels are caused by various conditions;such defective PV panels need continuous monitoring.The recent developm... Photovoltaic(PV)boards are a perfect way to create eco-friendly power from daylight.The defects in the PV panels are caused by various conditions;such defective PV panels need continuous monitoring.The recent development of PV panel monitoring systems provides a modest and viable approach to monitoring and managing the condition of the PV plants.In general,conventional procedures are used to identify the faulty modules earlier and to avoid declines in power generation.The existing deep learning architectures provide the required output to predict the faulty PV panels with less accuracy and a more time-consuming process.To increase the accuracy and to reduce the processing time,a new Convolutional Neural Network(CNN)architecture is required.Hence,in the present work,a new Real-time Multi Variant Deep learning Model(RMVDM)architecture is proposed,and it extracts the image features and classifies the defects in PV panels quickly with high accuracy.The defects that arise in the PV panels are identified by the CNN based RMVDM using RGB images.The biggest difference between CNN and its predecessors is that CNN automatically extracts the image features without any help from a person.The technique is quantitatively assessed and compared with existing faulty PV board identification approaches on the large real-time dataset.The results show that 98%of the accuracy and recall values in the fault detection and classification process. 展开更多
关键词 Photovoltaic panels deep learning DEFECT feature extraction RMVDM
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Perforation studies of concrete panel under high velocity projectile impact based on an improved dynamic constitutive model
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作者 Fei Zhou Hao Wu Yuehua Cheng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第9期64-82,共19页
The finite-depth concrete panels have been widely applied in the protective structures,and its impact resistance and dynamic fracture failures,especially the scabbing/perforation limits,under high velocity projectile ... The finite-depth concrete panels have been widely applied in the protective structures,and its impact resistance and dynamic fracture failures,especially the scabbing/perforation limits,under high velocity projectile impact,are mainly concerned by protective engineers,which are numerically studied based on an improved dynamic concrete model in this study.Firstly,based on the framework of the KCC(Karagozian&Case concrete)model,a dynamic concrete model is proposed which considers an independent tensile damage model and a continued transition between dynamic tensile and compressive properties.Secondly,the strength surface,equation of state and damage parameters of the proposed model are comprehensively calibrated by a triaxial compressive test with high confinement pressure,the rationality of which is further verified based on the single element tests,e.g.,uniaxial and triaxial compression as well as uniaxial,biaxial and triaxial tension.Thirdly,a series of projectile high velocity impact tests on thin and thick concrete panels are simulated,which indicates that the projectile residual velocity and dynamic fracture failures are reproduced satisfactorily,while the KCC model underestimates both the spalling and scabbing dimensions severely.Finally,based on the validated concrete model and finite element analyses approach,the validations of the existing five empirical formulae are evaluated,in terms of the depth of penetration(DOP)and scabbing/perforation limits of concrete panel.Both the Army corps of engineers(ACE)and modified National Defense Research Committee(NDRC)formulae are recommended in the design of the protective structure to avoid scabbing failure. 展开更多
关键词 Concrete panel PROJECTILE Dynamic fracture Scabbing limit Constitutive model
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Superiority of Bayesian Imputation to Mice in Logit Panel Data Models
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作者 Peter Otieno Opeyo Weihu Cheng Zhao Xu 《Open Journal of Statistics》 2023年第3期316-358,共43页
Non-responses leading to missing data are common in most studies and causes inefficient and biased statistical inferences if ignored. When faced with missing data, many studies choose to employ complete case analysis ... Non-responses leading to missing data are common in most studies and causes inefficient and biased statistical inferences if ignored. When faced with missing data, many studies choose to employ complete case analysis approach to estimate the parameters of the model. This however compromises on the susceptibility of the estimates to reduced bias and minimum variance as expected. Several classical and model based techniques of imputing the missing values have been mentioned in literature. Bayesian approach to missingness is deemed superior amongst the other techniques through its natural self-lending to missing data settings where the missing values are treated as unobserved random variables that have a distribution which depends on the observed data. This paper digs up the superiority of Bayesian imputation to Multiple Imputation with Chained Equations (MICE) when estimating logistic panel data models with single fixed effects. The study validates the superiority of conditional maximum likelihood estimates for nonlinear binary choice logit panel model in the presence of missing observations. A Monte Carlo simulation was designed to determine the magnitude of bias and root mean square errors (RMSE) arising from MICE and Full Bayesian imputation. The simulation results show that the conditional maximum likelihood (ML) logit estimator presented in this paper is less biased and more efficient when Bayesian imputation is performed to curb non-responses. 展开更多
关键词 panel Data IMPUTATION Monte Carlo BIAS Conditional Maximum Likelihood
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